Agent for reducing the surface



Patented Nov. 2, I948 AGENT FOR REDUCING THE SURFACE TENSIONS OF LIQUIDS Lee Lelserson, Chapel Hill, N. C., assignor to Virginia Smelting Company, West Norfolk, Va., a corporation of Maine Original application April 28, 1943, Serial No.

484,923, now Patent No.'2,404,913, dated July 30, 1946. Divided and this application May 14, 1946, Serial No. 669,500

4Caims. (01. 252-353) This invention relates to agents for reducing the surface tension of liquids and more especially to the use of these compounds as lifting and dispersing agents, to assist other surface active agents, such as wetting agents, detergents and 5v tion, it promotes rewetting on immersion in waother substances which promote wetting, peneter and promotes ease of handling in subsequent tration, swelling, frothing, and dispersing of matextile operations. In dyeing, the lifting agent terials by a solvent. This application is a divihas a great importance. It facilitates the dission of my co-pending application Serial No. persion of clumps-and aggregates of color par- 484,923, filed April 28, 1943, which was issued as ticles. It insures better solubility and the result Patent No. 2,404,913 on July 30, 1946. obtained is better and of more even color.

An object of this invention is the production Ketones can effect-lowering of surface tension of superior materials for effecting such changes but when they are combined with efficient wetting by combining these assistants with other surface agents and operate as lifting agents the mixture active materials. It has been found that the efnot only is more specific and effective than would fect of such combinations is more than additive be expected, but the lifting agent has a solvent and substantially increase the wetting, penetrataction, as above explained, which makes it an 8. Swelling. nothing and dispersing t n o excellent leveling agent for dye baths, and as the solution, and otherwise improve the action above t forth, assists by remaining t some of the materials with which they are associated. tent with the fiber in the future handling th The action of a wetting agent or any surface mat rials, active compound is primarily due to adsorption. Th liftin agents greatly increase the effective- If a textile IS. immersed in a solution With wetting ness of wetting agents and other surface active properties, the adsorbed air film on the surface is compounds in many fields of use, such as the pefirst displaced, due to the selective adsorption of troleum industry, tal processing, the paint i wetting agent molecules. Wetting agents, and dustry, cleaners and cleaning compounds, the rublifting agents, both reduce the surface tension ber industry agriculture-and cosmetics textiles of aqueous solutions. They do this because they both natural and Synthetic to give but a few have a limited solubility in water. The molecules fields f use: of the surface active compound are literally The single sheet f drawings is a table show, squeezed out from the interior of the liquid to the mg the increased emc-iency of wetting agent surface. The effectiveness of a particular comwhen mixed with the lifting agents. pound m reducing the surface tension depends A principal feature of the present invention reon theorientation of the molecules at theinter- Sides m the discdvery that ketones having 5 to face, liquid-air, and the disrupting effect this ori- 12 carbon atoms can be used effectively as assist ema'tmn has on forces between the water ants in conjunction with other materials with molecules at the interface. The best materials surface active properties such assodium alkyl effectively reduce the surface tension of water to sulfates" Sbdium oleate, 5013mm naphthalene that of ahydrocarbon. The reduction of surface sulfonates' andthenke. Toshowtheimportance of tension means that the liquid spreads easily and 40 these keto'nes asslstants or mug agents when quickly over a large surface. Thus, when a fiber ed 1th 0th w ttm a ht ther i subse is immersed in a wetting agent solution, the air, w e 8 e disc then oil or Wax, is displaced from the fiber due quently set orth proce me for a canvas to the selective adsorption of the wetting agent wetting test which procedure has been employed molecules. The solution spreads quickly over the with number of? cyclic ketones operating as large surface of the fiber and the wetting agent mg agentsem admixture w certain agents acts as a bond between two substances that might reducing the surface tension of liquids not otherwise adhere t each other, 7 data given hereinafter show the remarkable re- The action of a lifting agent, which is generally sults obtained by the use of these lifting a nt used in low concentrations where it would have so 2 has a solvent action for oils and waxes and facilitates their removal from the fiber, where a fiber is acted upon. As some of the lifting agent remains on the fiber after removal from the soluin combination with these surface active materials.

Canvas disc wetting tests are employed to comparethe wetting ability of various wetting materials. The following test was reported by Seyferth and Morgan in the American Dyestuif Reporter, 27, 525 (1938) andin Chemical Abstracts 32, 8789 (1938).

The test consists of measuring the sinking time of a 1" diameter, Number 6 canvas disc in a known solution. Conditions of temperature, concentration of wetting agent, water hardness and pH are controlled. The canvas used in these tests was natural color and unwaterproofed." All tests were made with discs cut from the same strip of cloth. to eliminate variations due to the canvas.

The solutions for the tests were made from a stock 1% solution. All were made with distilled water. The proper amount of concentrated solu- Another example of a combination which I have fond to possessexcellent properties follows:

Example 5 The use of alcohol is optional. but whenadded,

' the purpose is to produce a homogeneous mixture tion was measured into a 500 cc. volumetrio flask. An organic solvent, if any, was measured out and added. The mixture was then diluted with distilled water to 500 cc. This amount of the solution to be tested was, placed in a 600 cc. beaker. A Gooch funnel 1%" in diameter and having a barrel 3" long is inverted in the solution and the whole is brought to he desired temperature, usually degrees C. orking rapidly the Gooch funnel is removed, a canvas disc placed in the funnel which then is again inserted into the solution; at the same time a stop watch is started. The time recorded is that interval required for the disc to sink to touch the bottom of the beaker. After stirring the solution the test may be repeated for checks on the sinking time. To get consistent results it is necessary to insert the disc so that when it wets, one bubble of air comes off at a time from the same position near the edge -of the disc. I

Seyferth and Morgan report the deviation from mean wetting time to be 9.0%.

The tests which are reported hereinafter were conducted by the procedure Just above outlined.

The table in Figure 1 shows the results of the Seyferth and .Morgan canvas disc wetting test on solutions containing ketones as lifting agents, together with a wetting agent. All solutions contained 0.3 gram per liter of sodium ditertiary butyl naphthalene suifonate, as the wetting agent, made from an alkyl naphthalene fraction that had a boiling point of 185-495 C. at

5 mm. The concentration of, the ketone liftingagent was in no case large enough by itself to cause sinking the canvas disc in less than a matter of hours. The wetting agent was sufllciently concentrated to cause sinking of the disc in an average of about 63 seconds. The temperature of all solutions duringthe test was 25 C.

nate as a wetting agent --g. per Men.

.of the camphor and the wetting agent. Example 6 Sodium ditertiary butyl naphthalene suifonate, 4

Example .7

' Sodium ditertiary butyl naphthalene suifoprincipal surface active agent.

nate from a fraction boiling at -250 C. at 20 mm. and camphor in the ratio of 10: 1 g. per Men. 0.66

The addition of a cyclic ketone of from 5-12 carbon atoms to any surface active substance has an effect on the activity of the latter which is considerably greater than that which would normally be exerted by calculation from the surface activity of the separate components. The solutions of the mixture have an increased activity as regards wetting, penetrating, detergent, frothing and dispersing action. As specific examples which do not limit the scope of my invention, the surface active material may differ as widely as soaps, sodium alkyl naphthalene sulfonates, sodium alkyl sulfates, n-amyl ketone and sodium di-amyl naphthalene sulfate.

Saturated water solutions of ketones may also be used alone for wetting purposes, and in this use they may be employed not as lifting agents in combination with a wetting agent, but as the The preferred material for such purposes is a cyclic ketone having from 5-12 carbon atoms, in the form of saturated water solutions.

I claim:

1. A liquid, the surface activity of which has been changed, consisting of a solution of a sodium alkyl naphthalene suifonate and a cyclic ketone selected from the group consisting of camphor,

isophorone, cyclohexanone and 1,1,3 trimethylcyclohexanone.

2. A liquid, the surface activity of which has been changed, consisting of a solution of a sodium alkyl naphthalene suifonate and camphor.

3. A liquid, the surface activity of which has been changed, consisting of a solution of a sodium alkyl naphthalene suifonate and lsophorone.

4. A liquid, the surface activity of which has been changed, consisting of a solution of a sodium alkyl naphthalene suifonate and cyclohexanone.

LEE LEISERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,000,162 Ellis Aug. 8, 1911 1,967,656 Bertsch July 24, 1934 

